A roller-coaster normally has an endless track starting and finishing at a relatively low loading and unloading station. At the beginning of each circuit of the track the roller-coaster car or cars are moved up a relatively steep incline of an initial track section whose highest point is normally the highest point on the entire track. When released from this highest point the car gains considerable kinetic energy that allows it to remount smaller slopes to follow a circuitous and normally undulating path back to the loading and unloading station.
It is obvious that in order to create a ride with maximum drawing power it is necessary to operate at maximum speed, which is achieved by providing maximum initial lift for the roller-coaster car. To this end a heavy-duty ascent system must be provided which is capable of hauling the relatively heavy weight from a relatively low point to the high point of the track.
In smaller systems this is most simply achieved by providing a continuously driven endless chain that extends upwardly along the upstream side of what is termed the starting hill of the track. This endless chain carries a multiplicity of spaced-apart engagement elements that engage behind and push the car or cars up the hill, so that once these cars reach the summit of the hill they move over the peak and down the other side under the force of gravity. There is normally provided between the loading and unloading station and the very base of the first hill a sightly downwardly inclined track section so that once the roller-coaster car or cars are loaded they can be released from this loading station and will travel downwardly to the base of the starting hill where they will be engaged by the continuously moving chain and be displaced to the top of this hill.
Such systems are completely satisfactory for small-scale roller-coasters, and can even be used in relatively large nonportable systems. It has, nonetheless, been found extremely difficult to adapt these systems to the portable roller-coasters widely used today which are transported from one carnival or fair to another. Accordingly recourse has been had to systems not using a starting hill at all, but merely firing the roller-coaster car or cars off sling-shot fashion by means of a slider that is accelerated horizontally by means of a vertically displaceable weight that is slowly hoisted to the top of the tower standing alongside the track so that the kinetic energy of this dropping weight can be imparted to the roller-coaster car or cars.
The systems employed in portable roller-coasters have all proven relatively complex to assemble and disassemble. Not only must the assemblers be quite competent, but even so such a roller-coaster frequently takes an inordinate amount of time to assemble and disassemble. In fact as much as several days can be spent putting together a portable roller-coaster and another few days taking it apart for transport to the next site.